As a heads up for guys experiencing this - I've stopped exiting the game manually (ie. Windows key to desktop, closing the window) and instead have ESC-ed all the way back to the start menu, then one more time to actually exit the game. Since doing that I haven't had a corrupted profile again (touch wood). Might be worth a try - although I bet nows that I've said it I get one next time!
Thanks a lot for this! This issue has plagued me this week, this helped me get back to where I was a week ago! Cheers